Home Garden

How to Float a Boat House

Already constantly exposed to water, your boat can become a regular maintenance chore when you add in the effects of weather. A boathouse can provide welcome protection for your boat. Essentially a floating garage, a boathouse has walls on three sides and a garage-door type wall that provides a skirt, enclosing the slip and your boat when you're away. The floatation for a boathouse is constructed before the actual boat enclosure.

Things You'll Need

  • Carpenter's tools
  • 55 gallon plastic barrels
  • Pressure treated lumber
Show More


    • 1

      Using pressure treated 2-by-12-inch lumber, build a frame to enclose your plastic barrels, fastening the 2-by-12s crosswise with pressure treated 2-by-6s. The frame should surround a row of plastic barrels in a horseshoe shape you can think of as the foundation for your boathouse.

    • 2

      Fasten pressure treated joists to the barrel-frame so they line up in a flat plane just like the floor joists of a traditional wood-framed house.

    • 3

      Glue treated plywood, at least 5/8 inch thick, down to the joists using construction adhesive. Screw the plywood down with deck screws suitable for marine use -- either galvanized or corrosion resistant alloy.

    • 4

      Layout your bottom plate with a chalk line. Glue and screw the bottom plate and you can begin framing your boathouse.

    • 5

      Replace a boathouse flotation by building a plastic barrel float and moving an existing boathouse from its old, damaged flotation to the new float with a winch. Install two beams between the structure and the float, spanning from the old float to the new float. These will act as rails as you winch the structure to its new floating foundation.